received by the International Bureau on 13 April 2018 (13.04.18)

An electromagnet component for use in a generator, the electromagnet component comprising: at least one magnetic shoe comprising magnetite and a binder, the shoe being at least partially arcuate in cross-section; and a metallic core provided adjacent the magnetic shoe and operatively radially spaced from the magnetic shoe, wherein the at least one shoe has, or is, a sacrificial layer.

The electromagnet component as claimed in claim 1 , which comprises two magnetic shoes, namely an inner shoe and an outer shoe, each of the shoes comprising magnetite and a binder.

The electromagnet component as claimed in claim 2, in which each of the shoes has an arcuate cross section.

The electromagnet component as claimed in any one of claims 2-3, in which the shoes are operatively radially spaced relative to each other.

The electromagnet component as claimed in any one of claims 2-4, in which the metallic core is provided between the shoes.

The electromagnet component as claimed in claim 5, in which the core serves as a spacer to support the two shoes apart.

7. The electromagnet component as claimed in any one of claims 1 -6, in which the core is elongate and cylindrical.

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8. The electromagnet component as claimed in claim 7, in which the core has one of:

a round or rectangular cross-sectional profile;

a T-shaped cross-sectional profile; or

an I- or H-shaped cross-sectional profile.

9. The electromagnet component as claimed in any one of claims 1 -8, in which the core is of steel.

10. The electromagnet component as claimed in any one of claims 1 -9, in which at least one shoe includes a reinforcing component embedded therein.

11. The electromagnet component as claimed in claim 10, in which the reinforcing component is one or more of:

a mesh;

fibres; and/or

steel wire. 12. The electromagnet component as claimed in any one of claims 1 -1 1 , in which the binder comprises resin.

13. The electromagnet component as claimed in any one of claims 1 -12, in which magnetic particles in the magnetite are aligned.

14. The electromagnet component as claimed in claim 1 , in which the sacrificial layer takes the place of an air gap in a prior art generator.

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15. The electromagnet component as claimed in claim 14, in which the at least one shoe has two layers: a basal, non-sacrificial layer and the sacrificial layer which is a surface layer.

16. The electromagnet component as claimed in any one of claims 1 -15, which includes a dispersion layer which is metallic, the dispersion layer dispersing a magnetic flux or field which assists in creating a desired magnetic flux density and layout.

17. The electromagnet component as claimed in claim 16, in which a shape of the dispersion layer matches the shape of the at least one shoe, with the dispersion layer and the at least one shoe being in contact with each other.

18. The electromagnet component as claimed in any one of claims 1 -17, which includes windings coiled around the core.

19. The electromagnet component as claimed in claim 18, in which the windings are embedded in the at least one shoe.

20. The electromagnet component as claimed in any one of claims 1 -19, in which the magnetite comprises at least 90% magnetic particles.

21. The electromagnet component as claimed in any one of claims 1 -20, which has a +50% higher rate of magnetic flux change on its surface compared to prior art electromagnet components, the higher rate of change enabled by a combination of three parameters: (1 ) progressively decreasing an air-gap by a rate of 50% every quarter from a prior art airgap of 100mm to operating airgap of down to 1 mm; (2) changing at constant rate a surface area for the dispersion of magnetic flux so that the dispersion surface area becomes progressively bigger at the centre and smaller at the ends but not sharper; and (3) windings are more at the

3 bigger surface area and less at smaller surface area, the rate of change of windings being the same as that of the surface area.

An electromagnet assembly comprising plural electromagnet components as claimed in any one of claims 1 -21 , in which the plural electromagnet components are arranged side by side in a circle around an axis of rotation of a generator.

23. A generator including at least one electromagnet component as claimed in any one of claims 1 -21 .

24. The generator as claimed in claim 23, which includes plural electromagnet components, one electromagnet component for each pole of the generator.

25. The generator as claimed in claim 23, in which the plural electromagnet components are arranged side by side in a circle around an axis of rotation of the generator.

26. A method of operating a generator comprising the electromagnet component as claimed in any one of claims 1 -21 , in which electromagnet component bears against a relatively rotating component, and the relatively rotating component accordingly bearing against and thereby machining the electromagnet component to create a complemental fit with a minimal or no airgap.

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